The present invention relates to an apparatus for generating and projecting a bright, narrow color selectable beam of light for the generation of projected images.
In the past, a wide variety of devices have been utilized to generate a color beam of light by dispersing white light with a prism or by defraction grating. Such dispersions are commonly used in spectrometers and are less often used in generating projected images, such as words or objects, for producing artistic effects and for stage lighting and other applications requiring an intense narrow beam of white or colored light. It is much more common to utilize a beam of light through a colored filter for generating a colored light beam for these requirements and the colors may be changed by changing the filters and may be continuously varied by rotating filters in front of the light beam.
Typical prior patents which separate light into color components for various reasons can be seen in U.S. Pat. No. 3,659,918 for a color separating prism system and in U.S. Pat. No. 4,003,634 for an optical control assembly for a color design viewer which uses a single source of white light for five independent channels, each of which divides the light into three spectral components. In U.S. Pat. No. 3,907,430, an optical band pass filter uses a series of prisms and in U.S. Pat. No. 4,125,864 a beam splitter separates light into separate channels. U.S. Pat. No. 4,033,052 for an optical teaching aid is used for demonstrating the pure component of spectral colors of white light and the effect of selecting recombination of the spectral colors. It utilizes a diffraction grating to produce the spectrum from white light and then selectively filters the spectrum and then splits the light prior to recombination to project both an image of the selective filter and the new combined selectively filtered light adjacent to each other on a projection screen.
An aim of the present invention is to generate and project a bright, narrow color selectable beam of light which can be rapidly changed and which can produce a pattern of varying designs, as well as be connected for a rapid automatic control to produce constantly varying patterns, as desired.